Submission #1069915

#	Time	Username	Problem	Language	Result	Execution time	Memory
1069915		Unforgettablepl	Thousands Islands (IOI22_islands)	C++17	11.90 / 100	26 ms	6488 KiB

islands

#include "islands.h"
#include <bits/stdc++.h>
using namespace std;

variant<bool, vector<int>> find_journey(int N,int M,vector<int> U,vector<int> V){
    vector<vector<int>> adj(N);
    for(int i=0;i<M;i++) {
        adj[U[i]].emplace_back(V[i]);
    }
    vector<int> visited(N);
    bool found = false;
    for(int&child:adj[0]) {
        bool works = false;
        function<void(int)> dfs = [&](int x) {
            if(visited[x]==2)return;
            if(visited[x]==1) {
                works = true;
                return;
            }
            visited[x]=1;
            for(int&i:adj[x])dfs(i);
            visited[x]=2;
        };
        dfs(child);
        if(!works)continue;
        visited = vector<int>(N);
        if(found)return true;
        found = true;
    }
    return false;
}

• Subtask 1: 1.75 / 5
• Subtask 2: 1.75 / 5
• Subtask 3: 0 / 21
• Subtask 4: 8.399999999999999 / 24
• Subtask 5: 0 / 45